RAID, or Redundant Array of Independent Disks, is a technology of saving data on multiple hard drives which function together as one single logical unit. The drives can be physical or logical i.e. in the second case one single drive is divided into individual ones using virtualization software. Either way, the same information is kept on all the drives and the main advantage of using such a setup is that in case a drive breaks down, the data will still be available on the other ones. Having a RAID also enhances the performance because the input and output operations will be spread among a number of drives. There are several types of RAID based on how many drives are used, whether writing is done on all the drives in real time or just on a single one, and how the information is synced between the drives - whether it's recorded in blocks on one drive after another or all of it is mirrored from one on the others. These factors suggest that the error tolerance and the performance between the various RAID types can differ.

RAID in Website Hosting

The SSD drives which our cutting-edge cloud Internet hosting platform uses for storage work in RAID-Z. This sort of RAID is developed to work with the ZFS file system that runs on the platform and it works by using the so-called parity disk - a special drive where info kept on the other drives is copied with an extra bit added to it. In case one of the disks fails, your websites will continue working from the other ones and once we replace the faulty one, the info which will be cloned on it will be rebuilt from what is stored on the remaining drives along with the information from the parity disk. This is performed in order to be able to recalculate the bits of every single file properly and to authenticate the integrity of the information duplicated on the new drive. This is another level of security for the content you upload to your website hosting account together with the ZFS file system that compares a unique digital fingerprint for each file on all the hard drives in real time.

RAID in Semi-dedicated Servers

The information uploaded to any semi-dedicated server account is kept on SSD drives that function in RAID-Z. One of the drives in such a setup is used for parity - whenever data is cloned on it, an extra bit is added. In case a disk happens to be defective, it will be taken out of the RAID without disturbing the work of the Internet sites since the data will load from the rest of the drives, and when a new drive is added, the info which will be copied on it will be a combination between the info on the parity disk and data saved on the other hard disks in the RAID. That is done so as to guarantee that the info which is being duplicated is correct, so as soon as the new drive is rebuilt, it could be integrated into the RAID as a production one. This is one more warranty for the integrity of your information as the ZFS file system which runs on our cloud web hosting platform compares a unique checksum of all of the copies of the files on the different drives in order to avoid any chance of silent data corruption.